Two sisters from Illinois have described how it feels to rot from the inside out after using the flesh-eating drug krokodil.

Amber and Angie Neitzel from Joliet, a suburb around 40 miles from Chicago, were two of five people admitted to hospital after using krokodil.

The drug, which emerged in Russia around 10 years ago, is similar to heroin but is much cheaper as it is made from everyday household products such as lighter fluid, gasoline, paint thinner and codeine.

Speaking to ABC, Amber said she first noticed wounds on her skin around a year-and-a-half ago: "It almost starts like a burn from a cigarette. It starts purple and then goes into a blister after five or six days."

Krokodil has been dubbed a zombie or cannibal drug because it eats users flesh from the inside out. The average user has a life expectancy of just three years.

"You can get marks and bleeding from shooting up heroin, but nothing like this. They are deep holes and the skin is just rotting away. It's hard to describe how revolting they are," she told the Mail Online.

"This is a really bad problem. This drug is real, it rots you away from the inside and attacks your organs.

"I have been using for 18 months and I know it's done some permanent damage. I will be lucky if I live another ten years from now.

"My boyfriend actually had maggots coming out of his leg. I know people don't want to hear stuff like that, but it is really happening out here."

The drug dissolves user's jawbones and teeth, causes blood vessels to burst, which leaves skin green and scaly - where it got its name as users begin to resemble reptiles.

Angie's wounds became so bad she had to have emergency surgery to save her legs: "I'm scared to death right now. I can barely leave my house. I have to go to an infectious disease doctor, decide how much it's progressed and wind up doing skin grafts."

Their mother, a recovering heroin addict, told their daughters to seek medical attention after she believes she took krokodil that had been sold as heroin: "Four weeks later I went to the hospital. They surgically removed it, but at the time they didn't know it was crocodile. They just thought I messed with a dirty needle or something like that."

Speaking to CBS, she added: "Amber stopped shooting in her legs a little over a month ago, because it was making black spots everywhere."

Dr Abhin Singla, a drugs expert at the Presence Saint Joseph Hospital, where the sisters were treated, told the Mail Online he recognised krokodil straight away: "The moment I saw Angie I knew what she had been taking. It was Krokodil without a shadow of a doubt. All the symptoms matched up 100%.

"I have friends in Russia and I have been following this for some time, I was extremely worried it would come over to the US and now it has. The sores are very different to anything else, they go right down to the bone. It is extremely graphic and worse than anything I've seen before.

"The effects are the worst I have ever seen from any drug in all my years of practise. It takes hold and does damage so fast. I expect to see a lot more in the coming months because I believe this will spread.

"The people I have seen have not known what they were taking, but I believe some addicts will take it by choice despite the effects. There is an intense high and it's cheap, if people are desperate enough, they will use it."

Meanwhile it is thought krokodil has claimed at least one life in the US following an investigation into the deaths of two men in Oklahoma who have been linked to the drug.

Chelle Fancher, a friend of one of the deceased, told KOCO Oklahoma City: "(His) skin was missing. The doctors say it ate him from the inside out. It wasn't until the next day that they told us that is was Krokodil meth."